PN junctions in nanoscale materials are of interest for a range of technologies including photodetectors, solar cells, and light-emitting diodes. However, Schottky barriers at the interface between metal contacts and the nanomaterial are often unavoidable. The effect of metal-semiconductor interfaces on the behavior of nanoscale diodes must be understood, both...
Ion channels play a key role in regulating cell behavior and in electrical signaling. In these settings, polar and charged functional groups, as well as protein response, compensate for dehydration in an ion-dependent way, giving rise to the ion selective transport critical to the operation of cells. Dehydration, though, yields...
We study photocurrent generation in individual suspended carbon nanotube pn junctions using spectrally-resolved scanning photocurrent microscopy. Spatial maps of the photocurrent allow us to determine the length of the pn junction intrinsic region, as well as the role of the n-type Schottky barrier. We show that reverse-bias operation eliminates complications...
This thesis looks at the third harmonic voltage response of a small incandescent lightbulb. The third harmonic voltage, or 3 omega (3ω) voltage, arises from applying a 1ω sinusoidal voltage across a resistive material. The 3ω voltage carries with it information about the thermal conductivity of the material. A lock-in-amplifier...
Investigations of the effect of cold working on the
internal friction of copper have become numerous in the last
few years due to the discovery that part of the internal
friction is due to the motion of dislocations in the metal.
Most of the investigations so far have been done...
Sound waves are very convenient for the investigation of
all wave phenomena with the exception of polarization. They are
particularly useful in connection with microwaves because the
latter's wave length can be easily duplicated with sound waves,
making it possible to obtain the same diffraction pattern for
both when confronted...